Currently, wireless communication service has developed from a low speed voice service to a high speed multimedia data service. In order to meet a growing requirement on high capacity and high data rate, in addition to applying a wireless access technology with a higher capacity and a higher transmission rate, operators usually provide a basic network coverage and further deploy a base station or cell of different standard or different modality in the same region for capacity boosting. A network providing the basic network coverage is referred to as Network One, and a network formed by a base station or cell providing capacity boosting is referred to as Network Two herein. For convenience of description, the base station or cell of Network One is referred to as a coverage base station or cell (Coverage Base Station), and the base station or cell of Network Two is referred to as a capacity boosting base station or cell (Capacity Boosting Base Station) hereinafter.
As shown in FIG. 1a, micro/pico base stations (Micro/Pico Base Station) B, C and D of Network Two are deployed at hot spots in a coverage of a macro base station or cell A of Network One for the purpose of capacity expansion, in this case, the base station or cell A of Network One is a coverage base station or cell, and the base stations or cells B, C and D of Network Two are capacity boosting base stations or cells. As shown in FIG. 1b, a macro base station or cell F of Network One provides a basic network coverage for a certain region, and a macro base station or cell E of Network Two is a co-site base station or cell with the base station or cell F to perform capacity boosting, in this case, the base station or cell F of Network One is a coverage base station or cell, and the base station or cell E of Network Two is a capacity boosting base station or cell. As shown in FIG. 1c, a macro base station or cell of Network One provides a basic network coverage for a certain region, and a macro base station or cell of Network Two is deployed in a coverage of Network One to provide capacity boosting in the region, but does not a co-site base station or cell with the base station or cell of Network One, in this case, the base station or cell of Network One is a coverage base station or cell, and the base station or cell of Network Two is a capacity boosting base station or cell. Network One may be a GSM/EDGE Radio Access Network (GERAN) or a Universal Terrestrial Radio Access Network (Universal Terrestrial Radio Access Network, UTRAN), and Network Two may be an Evolved Universal Terrestrial Radio Access Network (E-UTRAN). Network One has a different standard from Network Two.
In the above description, a coverage base station or cell and a large number of capacity boosting base stations or cells are deployed to satisfy the requirement on high capacity and high data rate, accordingly, power consumption is increased. Therefore, power saving for a wireless network is a problem to be addressed urgently.
In a conventional power saving method for a base station, a management system notifies a base station to perform a first predetermined operation, i.e., entering a complete dormant state or shutting down automatically, if load of the base station is less than a certain threshold; and notifies the base station to perform a second predetermined operation, i.e., waking up or starting up automatically, if load of a neighboring region overlapped with the coverage of the base station is greater than a certain threshold.
In another conventional power saving method for a base station, a coverage base station or cell activates all capacity boosting base stations or cells in a dormant state within a coverage of the coverage base station or cell when the coverage base station or cell detects that its load is high; if some of the capacity boosting base stations or cells can not effectively absorb the load of the coverage base station or cell after being activated, these capacity boosting base stations or cells enter the dormant state to save power when a condition of entering the dormant state is satisfied again.
Two problems may be caused when these two power saving methods for the base station described above are applied. Firstly, in a case where a user of the coverage base station or cell initiates a short-term service that only can be born by the capacity boosting base station or cell, the service can not be born by the network if the capacity boosting base station or cell does not start up because the current total amount of load of the coverage base station does not reach an amount that causes the capacity boosting base station or cell to start up, and user experience is seriously affected. Secondly, even the capacity boosting base station or cell can start up in a timely manner to bear the service, the capacity boosting base station or cell may enter the dormant state again due to a less amount of the load after the service is finished. If there are a large number of such users and these users are dispersed, the capacity boosting base station or cell will frequently start up and shut down. During this process, a user in an idle state frequently initiates a different standard reselection, which increases power consumption of the terminal and causes a serious signaling impact on the network by a different standard update (such as RA/TA) for the different standard reselection.